1. Field of the Invention
The present invention relates to 3D Image Display, an aligning system and method thereof.
2. Discussion of the Related Art
The 3D (or “Three Dimensional”) video display device is a system for representing 3D video data artificially. It comprises the software for generating and/or processing 3D video and the hardware for representing the 3D video contents generated by the software.
The 3D video display device is classified in the stereoscopic display and a autostereoscopic display depending on whether the observer should wear an specific glasses or not.
As display device for the stereoscopic display system is replaced from the cathode ray tube (or CRT) to the flat panel display, the technology of stereoscopic type is developed to be optimized for the flat panel display. Typically the stereoscopic display uses polarization technology. In the polarization technology, polarization films or plates having different polarizing axes are applied to the glasses for the left and right eyes, respectively. The polarized light for the right eye is blocked by the polarization film or plate on the left eye. At the same time, the polarized light for the left eye is blocked by the polarization film or plate on the right eye. Even though the stereoscopic display system requires polarization glasses and has a lot of light loss, it can get wider view angle. Therefore, it has advantages to apply for the most common 3D display system, to develop with low cost and to make large system.
The autostereoscopic display system does not require any polarization glasses. However, it has restricted view angle so it is hard to develop for large display system such as theather system. Typically the autostereoscopic display system uses the parallex barrier technology. In the parallex barrier technology, the left image for the left eye and the right image for the right eye are alternately represented behind the apertures of which shape is thin slit shape called the barrier. Therefore, when an observer sees the images through the apertures, the left image can be seen by the left eye only and the right image can be seen by the right eye. The parallex barrier technology is not using the optical technology such as polarization technology but separating the left image and the right image with the barriers.
The most important problem for mass production in the 3D video display device is to establish the technology for aligning the 3D filter separating the lights of left image and the lights of right image on the display element.
The typical method for aligning the 3D filter with the display panel in the stereoscopic display system is to repeat the aligning operation until the image shown on the display panel is correct by operating the display panel and wearing the polarization glasses.
A company called Master Image Inc. suggested, as shown in FIG. 1, the method for aligning the parallex barrier 20 and the display panel 10 (KR Patent No. 10-0709728). In this method, with two image capturing devices (CAM1 and CAM2) apart from the display panel 1 and the parallel barrier 2 with a predetermined distance, the 3D image shown on the display panel 1 is captured. Checking the separated situation for the left image and right image of the 3D images, the alignment between the display panel 1 and the parallex barrier 2 is repeated until the alignment is satisfied with the predetermined quality.
Like this, the method for aligning the 3D filter with the display panel by deciding the image shown on the display panel with users eyes, or the method for aligning the 3D filter with the display panel by checking if the image acquiring through the vision system using 2 image capturing devices is separated with satisfying certain criteria needs to supply electric power to the display panel and to apply the data of test pattern images for checking the alignment. Therefore, the two methods are hard to establish an exactly quantized alignment level. Further, as the driving system and signal controller are required to drive the display panel of the aligning system, the equipment cost is expensive. In addition, it takes much time for aligning process so that the productivity is degraded.